MAGNESIUM-SULFATE OR NIFEDIPINE HYDROCHLORIDE FOR ACUTE TOCOLYSIS OF PRETERM LABOR - EFFICACY AND SIDE-EFFECTS

Objective: To compare nifedipine and magnesium as initial and long-ter m tocolytic agents. Methods: In this prospective study, 90 patients wi th documented preterm labor over an 18-month period were randomized to receive oral nifedipine (n = 50) vs parenteral magnesium (n = 40). If tocolysis was successful, oral therapy using nifedipine or magnesium (gluconate) was continued. Results: Both groups demonstrated clinicall y significant prolongation of pregnancy from the time of initiation of therapy (magnesium = 43 +/- 34 day; nifedipine 37 +/- 26 day). There was no difference in the preterm birth(n = 18 in both groups) or low b irth weight (<2500 g, magnesium = 19, nifedipine = 15). There were no hypotensive side effects or fetal complications of nifedipine therapy, and no patient was removed from long-term therapy for side effects. G astrointestinal side effects were responsible for discontinuing oral m agnesium therapy in three women. Conclusions: These data show that bot h nifedipine and magnesium are effective as a first-line tocolytic the rapy. No evidence of fetal, neonatal, or maternal compromise was noted in either group.